Deletion of <i>SphK1</i> gene reduces multi-walled nanotubes-induced granulamatous inflammation in mice.

<p>8 weeks old male C57BL6/J wild type and <i>SphK1^−/−</i> null mice (n = 6 in each group) in the same background were intraperitoneally injected with either sterile PBS or PBS containing 50 µg or 3 mg of MWNT as described under “Experimental Procedures”. After 12 days, mice were anesthetized, diaphragms were dissected, fixed with methanol/chloroform/glacial acetic acid and paraffin-embedded sections were stained with hematoxylin/Eosin. (A), Diaphragms from sham operated wild type and <i>SphK1^−/−</i> mice show no granulamatous inflammation. (a and d), C57BL6/J mice were exposed to 50 µg or 3 mg MWNT show the presence of granulamatous inflammation on diaphragms. (b and c), <i>SphK1^−/−</i> null mice exhibit reduced granulamatous inflammation. (e and f).